Bion-x hack: removing the limiter

A factory Bion-x kit has the 32 km/h limiter in place to conform with the law. What happens is that the controller detects the RPMs of the motor wheel and using the wheel circumference, as entered in the setup menu, it determines the current speed.

If the speed goes over 32 km/h the controller will cut the power to the rear wheel until the speed drops below 32 km/h at which point it will send power to the rear wheel again. So it pulses at the limit. on, off, on, off and so on when you get to the speed limit.

This speed limiter can be disabled by changing the settings in the 3773 setup menu. Consult your Bion-x manual to find out how the setup menu works. This is where you can set the date, tire size and so on.

When the limiter is disabled there will be no pulsing at the limit. The bion-x will simply keep powering the bike to its maximum. You only gain a few more km/h before you hit the power limitation of the motor.

What about legalities? Well, you are going faster under assist power than the law states but most police officers won't bother you anyway.

This document contains procedures and information that gives access to all
configurable parameters and hidden options of the BionX system. It is intended to the bike shop and BionX installation technicians.

This paper covers the console firmware revision #12 and higher. All the previous firmware revisions do not include all the functions mentioned in this document and/or the menu structure can be different.

If you own a system with older firmware, we recommend you to call EPS to get assistance as needed. However, it is also possible to upgrade the firmware on all BionX systems. (It is important to remember that the system performance is the same regardless of the firmware versions.)

2. How to enter a particular code

All following sections of this document use 4 digit codes. Whatever the user wants to access the configuration menu (3771), diagnostic screen (3772) or remaining variables (3779) the same method must be used:

1. Turn the system ON.

2. Hold down both ‘CHRONO’ and ‘MODE’ buttons at the same time until the
screen change to four zero (It takes about 2 seconds)

3. Using ‘A’ to increase the digit value and ‘G’ to decrease value, enter the first digit.

4. Push ‘MODE’ once to advance to the next digit.

5. Repeat step #3 and #4 for all remaining digits.
* If an invalid code is entered, the display will simply return to the normal display layout.

2. If the 3771 code is correctly entered, you will see four digits that represent the actual wheel circumference in millimetres. If the user wants to keep the old circumference value, the same digits must overwrite the old ones. If a new wheel circumference has to be programmed, enter the new value. Use the following table to convert wheel diameters in inches to circumference in mm.

3. The next configuration screen is the unit configuration. Either ‘A’ or ‘G’ can be pushed to switch from imperial to metric:
• will select metric unit (kilometres)
• will configure the bike to imperial system (miles)

Push ‘MODE’ button when done to advance to the next configuration screen.

4. The third screen is used to configure the speed limit.

• Two parameters can be configured regarding the speed limit process:
Activation or not of the function and the limit level in km/h.
i. Pushing the chrono button will switch between the two
parameters.
ii. Use ‘A’ and ‘G’ to configure the speed threshold value or the
function state (0=no speed limit, 1=speed limit enabled)

Push ‘MODE’ button when done to advance to the next configuration screen.

5. The fourth menu is used to configure the braking generation level when the rear brake is applied. Use ‘A’ and ‘G’ to set the desired value. The configurable range is from 5 to 64. 64 will generate maximum breaking power while choosing a lower value will produce less regeneration breaking.

Push ‘MODE’ button when done to advance to the next configuration screen.

Follow second section instructions to enter the EPS2 code. Screen will switch to a special ‘diagnostic’ mode where it is possible to monitor some important signals:

• Strain gage sensor value: (Cyclist effort sensor) when the cyclist push on the pedals, this signal will raise proportionally to the force applied.
• Battery voltage: Indicate the NIMH battery voltage in volt.
• Monitor the motor command: While the bike is operated, the assistance or generation level will appear on the two upper-left digits. Again, the values range if 0-64.

There is two ways to exit the special diagnostic display mode:

• Simply turn the system off. Next power ON will display normal layout.
• Re-enter the 3772 code will toggle display to normal layout.

8. EPS9 – Remaining time & Distance (3779)

BionX development team is always improving the product reliability and
performance. One of the latest add-in on the system firmware is the possibility to be informed about the remaining time and distance at any time, based on the last 10-20 seconds of bike utilisation history. This function being relatively new and presently under beta testing phase, is not available by default on a brand new system. However, BionX gives the possibility to access this feature for the users who wants to experience it.

Once again firmware revision #12 and more are a requirement to access the new variables. By entering a special unlock code, the users will have access to two more display variables:

• Remaining time:
As the user cycle to all different variables by pushing ‘chrono’ button, the prefix ‘Tr’ will appear. Tr stand for ‘Time Remaining’ (or Temps Restant in French). The unit is in hour with tenth of hour precision. The following example shows a remaining time of 4 hour 30 minutes.

• Remaining distance:
The variable name prefix is ‘dr’ (distance remaining, or distance
restante in french) and the value are in kilometres (or in miles if console
configured to imperial units). The following examples show a remaining
distance of 168 kilometres.

The procedure to unlock the feature is simply to enter the EPS9 code (3779) as mentioned into the second section of this document. The function becomes instantly accessible. Recycling the power is recommended after enabling the function. If the user wants to disable the function, it can be toggled ON and OFF by entering the same code again.

Since both variables require microcontroller processing time and multiples
operations, under certain conditions, one or both variable cannot be predicted. Per example, if the bike is stopped and the speed is null, remaining distance cannot be processed. Another case could be if the user use the regenerating brake for more than a few seconds, the remaining time would be infinite. In those particular cases, the value of either variable is replaced by three dash character (---). The picture below display an incalculable remaining distance:

9. Important notice about speed limit

Almost all BionX kits that have been released today are running firmware #12 and later. Regardless of the country, the laws are very strict regarding any electric bicycle speed limitation. Even if this guide give the user the possibility to configure or even remove the speed limit algorithm, EPS will not be responsible for any accidents or wounds that could results of an improper or non legal speed limit configuration.

All the bicycle kits sold from EPS are already configured to offer the maximum legal permissible speed for each corresponding countries. The limits are the following:

- America: 32 km/h or 20 mph
- Europe: 25 km/hr or 15.5 mph

All future firmware releases from EPS will avoid the user to play with the speed limit parameters.

I wish the Bionx motor could churn out 250W (or even 100W) when I'm cruising at 20mph without the assistance. It can easily kick me into the upper 20's. Ahh, but the stupid laws.... I believe Optibike claims that thier bikes are legal because the motor assist alone can get you 20mph. Your legs can add the extra speed (on top of the 20).

I wonder if there's a way to use the 36V battery with the 250W motor to get the extra speed. (just wishful thinking).

Anybody know how to re-enable the thumg throttle? I seem to have lost it after doing a reset (code 5000). I was able to re-configure everything else but I couldn't find any menu to re-enable the thumb throttle.

I think it may be some button combo that needs to be pressed during power on or something.

Also of note; browse this site and find many "Hidden" Bionx documents and files RIGHT HERE.

Check out the /file and /file/tech/ folders. Really useful stuff in there.

THROTTLE ENABLE PROCEDURE

If your Bionx has a thumb throttle and for some reason it no longer works, like using menu code #5000 (full reset), here's how you get the thumb throttle back:

1 - Start your Bionx like you normally do.
2 - Press and hold the MODE and -G buttons for 2 seconds.
3 - A countdown will start. During the countdown, press and hold the thumb throttle all the way down.
4 - When countdown reaches 0, release throttle.
5 - Press Mode button again to shut down the system. This will save your settings.
6 - Turn the system back on and test the throttle to make sure it still works.

My own personal settings. After I do a full reset, menu code 5000, I follow this list to set my PL350 back to my personal preferences. This is the way I like mine to be. I don't want the system to hold back, I like it to give full power at all speeds. My reasoning is simple: If you don't like the thumb throttle, don't use it; if you think assist 4 is too much, then lower it. You decide.

I use a PL350 ( 350W motor with 36V Li-Ion battery) on a mountain bike with 26" wheels. My firmware is Rev:2.3

Initial Setup

Throttle
Turn on system
Press Mode and -G for 2 seconds
During countdown, press throttle lever all the way down
Once throttle reaches 0 , release throttle
Turn off system

Choose PIN
Press and hold +A and -G for 2 seconds
Using +A and -G keys, choose digits
Press Mode to select digit and move to next digit

Configure menus
Press and hold Mode and Chrono buttons for 2 seconds to get into menu system.
Use +A and -G to set each digit and press Mode to go to next digit
Use +A and -G to select options for each menu
Some menus have extra options which can be selected with Chrono button
Press Mode button to save changes and exit programming menu
0007 : Set to 3.0
0008 : Set "A" to 4.0, Set "B" to 1.0
1234 : Sensor speed signal , set to 4
1970 : Configuration backlight. Set to OFF
1976 : Motor direction. Set to 1 (forward)
2001 : Set to km/h
2002 : Generative braking, set to max (64)
2003 : Activate battery remain display (toggle)
2004 : Set the clock to current time
2005 : Set wheel size to 2075
2006 : Brake sensor, set to ON
2007 : Polarity throttle, set to 0
3771 : Set wheel size to 2075
3773 : Max speed (assist), set to OFF
3774 : PR ? set to ON
3775 : Max speed (throttle) , set to OFF
3776 : Speed motor will start, set to OFF
3779 : Time and Distance remaining display, activate if not active already.

Hope this helps, if you find any paticular settings are better with different values on your own system, please share with the rest of us.

Thanks

Edit: Revised values for setting 0007 and 0008. I've found that 1.0 for menu 0007 is too low and the controller often doesn't detect the cyclist pedaling. Setting to 3.0 will allow the controller to detect the cyclist earlier and be more sensitive to changes in cyclist torque output.

Diagnostic mode (menu 3772) allowed me to find that the "B" option on menu 0008 is best to be set to 1.0 rather than 25.0. I think this is the speed where the extra assistance kicks in. If this is the case, it's probably better to have it kick in at a lower speed since you're not likely to be climbing a steep hill at 25 km/h. I also noticed the assist power (upper left digits in diagnostic mode) were higher with the 1.0 value and seemed to climb faster from a complete stop.

I have REU23 and tried everything up above to increase the speed but I am still stuck around 22MPH max electric only speed. Anyone know why? The energy bars start dropping from 17MPH and up by the time it gets to 20MPH there is only 1 or two energy bars, so I am thinking it could provide more. The only reason I can possibly think of for this is voltage. If the kV of the motor is just so than the motor may be generating 32Volts. If that is the case than the controller is not going to be able and help me, because the once the motor voltage "back EMF" is equal to that of the battery, than you have reached absolute top speed.

That being said, does anyone know exactly what powerMOOSFETS are being used in the ESC on this thing? What is the absolute maximum voltage that this system could tolerate? Could I use my tanic pack lithiumpolymer batteries and make a "48Volt" pack (that would actually be a full charge max of 50.4Vdc for a 12Cell LiPoly pack)?

I have just installed a Bionx kit on my bike, and I would also like to see more assist when cruising at 20 mph. I have firmware 1.5, so I do not have the speed limit removal code 3443 or the torque sensor gain 0007 on my console.

Mace on the Tidalforce google forum has recently reported on using a 39.6V A123 custom battery pack in his 36V system. He reported that the ride went about 20% faster. Tidalforce bikes can also be overvolted into the 40s as reported on endless sphere. I would be very interested to see how the system performs at higher voltages. A 13S A123 pack would give 42.9V, for example.

I am a little confused by the reports from Bionxrider and Zeuser regarding the amount of assist above 17mph. Bionxrider reports diminishing assist to near zero by 20 despite having removed the speed limitation, while Zeuser reports full assist up to a little over 20mph. Zeuser, what energy bars are you seeing on your console when you push the speed up? In the interests of science, perhaps both of you could perform one simple experiment and report back what the no load max speed is when you lift the rear wheel and max out the throttle on your systems. I have no throttle, so I can't try it.

When I'm traveling about 38 km/h in assist mode #4 I see about 3-5 bars on the assist graph. It varies a bit, it goes up and down, but I can sustain 38 km/h with the assist. If I turn assist down to 3 I can maintain about 32 km/h. By pedaling alone (no assist) I can maintain about 27 km/h without exhausting myself.

I've done the no load max speed and it's 38km/h without the limiter. That's where the motor just doesn't have the power to spin any faster. I'm told that's a limitation of brushless motors.

Keep in mind that this is very un-scientific since I'm taking into account error margins. And the Bionx speed is a bit optimist if you follow their settings. My GPS registers about 1km/h lower speeds than the Bionx. And my handheld GPS matchs up with my car's navigation system and speedometer.

26" wheels

Yes my bike is a fuji discovery-2 2004 mountain bike. It has 26" wheels and I am now looking into getting a decent 700c road bike to transfer my system onto. I can assure everyone who is interested there is no inherent limit to brushless motors in the general sense. It is that any dc motor is also a generator. the output voltage of the motor (generator) when spinning is directly proportional to the RPM it is spinning at. Once the RPM of the motor is fast enough that the output of it is equivalent to the voltage of the battery system being used to drive it as a motor, then you have reached the maximum rpm of that system. This is a fact.

When I lift the back and hit the throttle my speed with a full charge goes to 25.9MPH! That is with the battery measuring 41.9Vdc. when I let the battery get down to 38Vdc then the same test yields a no load speed of 22MPH. In both cases the current meter bargraph drops to zero immediately and remains there while the speeds maintains those cited above.

Taken from there component price sheet. Notice how the description of the various motors they sell includes an RPM? I am assuming that is the max RPM for the system voltage that each particular wheel will do...so, one could potentially buy the motor for the 20" wheel and re-thread it onto a 700c wheel for a potential of 385*Pi*27.559"*60/12/5280=31.565MPH !!

(That is Revolutions Per Minute times Pi (3.141) times diameter of 700c wheel * 60 minutes in an hour divided by 12 inches in a foot and divided again by 5,280 feet in a mile)

This says the hypothetical max speed of my 350 watt motor/wheel/bike at nominal voltage is 23.2MPH. that is about right. It would be fun to go 32 before adding human power though?!

Were you using a standard Bionx 36V lithium battery? I am pleasantly surprised that it produced 41.9V at full charge, maybe 48V would be within the limits of the system if some care is taken not to overheat the motor.

Where did you place the voltmeter leads to test the battery? My battery has two main power terminals (the large ones on the left and right of the battery connection) which show zero volts when removed from the bike, despite the battery being full and my voltmeter is definitely working. I can get a reading that seems low (23V when the console voltmeter displays 25) by connecting the voltmeter leads to a pair of smaller "control" terminals on the battery.

If the 350W motor were identical to the 250W motor, it should run at 50% higher rpm when driven by a 36V battery as a motor has a constant V/rpm based on overcoming back-emf as you describe. In reality the two motors are physically different, as the 350W motor weighs 1.1 pounds more than the 250W motor. My guess is that more wire is wound into the larger motor to produce more torque, and this lowers the top rpm. But would it really limit the increase in rpm to 7% (280 rpm to 300 rpm) when it would otherwise climb by 50% based on the voltage increase? And what about the 350W motor that is rated at 385 rpm, is it really that different internally?

I suspectedhat Bionx hadan internal rpm limit built in to the controller or motor which could not be removed by the user. In effect, a master speed limiter that exists underneath the console options like "max speed" 3773. How else would it be that nearly all Bionx motors "hit the wall" at 18-22mph, given the variety of voltages during discharge and wheel sizes and types used on the bikes and rider weights, even after the 3773 limitation has been removed? OTOH, your test shows a 10% drop in voltage caused a nearly 20% drop in no-load rpm, so it doesn't appear that a speed governor was limiting your system.

I have also considered trying the 385 rpm motor in a larger wheel and then raising the voltage into the 40s with an A123 battery. Perhaps someone has already tried one or both of these mods?

My goal is to achieve a 25 mph cruising speed on my Stumpjumper with high pressure slicks and no wind while pedalling at 175-225 watts using a Bionx system with no throttle to interfere with my steering, braking, and shifting.

Bionx default codes

Hi Zeuser,

I have tried the codes you 've given.
I have very good speed but the bike is too responsive and the battery consumption increased accordingly.
I found that there is less difference between different levels of assistance.
I didn't put down all the default codes. Don't want to do the full reset either.
So what's the initial settings of : 0007;0008;1234;2002;2006?
Anybody tried to change the codes?
Thanks

I know this an old thread, but has anyone figured out how to do this (remove speed limiter, or up it to 40 KMs) on the newer models...? On mine it just shows the speed set to 1 - 32 KMs, and won't change...

I know this an old thread, but has anyone figured out how to do this (remove speed limiter....

I have not figured out how to do it, but if I were set on doing it, the easy hack would be to fool the system by setting the wheel size smaller. Of course, everything your console tells would be off by as much, rendering it useless. Meanwhile the wind blows through your long golden locks as you frolic along enjoying speeds only your beer swilling friends can tell you from a speedometer of a '67 Mercury trailing alongside on a country road, full of potholes and vertical grates.

I have not figured out how to do it, but if I were set on doing it, the easy hack would be to fool the system by setting the wheel size smaller. Of course, everything your console tells would be off by as much, rendering it useless. Meanwhile the wind blows through your long golden locks as you frolic along enjoying speeds only your beer swilling friends can tell you from a speedometer of a '67 Mercury trailing alongside on a country road, full of potholes and vertical grates.

Ha, Ha... I may still try that, seeing that I also have my old speedometer still on my bike and won't have to guess how fast I am "actually" going, 32 KMs is just a bit too slow... I feel like 40 KMs/Hr would be a big step towards satisfying me, as then my E bike purchase/upgrade would then be worth it... I guess there are just too many people making a living writing laws that don't necessarily need to be written... JMO

My 2012, SL 350 ht DT XL goes 32kph and my range is over thirty miles. Resetting the speed limiter would reduce my range and probably void my warranty. I'm already faster than 99% of the bikes on the path, so I won't be playing around with resetting the programming anytime soon. Ebikes are struggling for a foothold in my city and speeding in the bikelanes would only make it worse. My aluminum frame, cro mo forks and Schwalbe tires are not rated for much more speed anyways, and I got two wheeled speeding out of my system after many years of motorcycling (and motorcycle crashing). If you want to go fast, buy a GSXR.
Secret to happiness: want what you have.

I have not figured out how to do it, but if I were set on doing it, the easy hack would be to fool the system by setting the wheel size smaller. Of course, everything your console tells would be off by as much, rendering it useless. Meanwhile the wind blows through your long golden locks as you frolic along enjoying speeds only your beer swilling friends can tell you from a speedometer of a '67 Mercury trailing alongside on a country road, full of potholes and vertical grates.

Tried it today, set it to a smaller wheel size but the end result was same actual speed but slower speed shown on speedometer...

He uses statistics as a drunken man uses lamp-posts...for support rather than illumination. I do like my beer, so sometimes I do end up leaning on the lamp-post...